First of all, an intro to radio controlled boats

There are about as many types as people – the most common ones are scale, function, racing. Scale – this means that the boats are built to look like a real-life boat, these can be bought at horrendous prices but can, with a lot of love and work, be made at home:
ROBBE-Stromaufsichtsboot-Bussard-0-90m-0111196_b_0The second type I mentioned is function, these boats are scale but have scale functions such as anchors, un-loading cranes and more, usually these are even more expensive, only experienced modellers can make the functions work on homemade boats:
1194_9Last but not least – the most common, racing, these boats usually do not have a real-life counterpart, and are fast and maneuverable, many do not have reverse:
maxresdefaultThe boat I built would probably be a scale boat, it is built after  several real life yachts,from each I took the best bits to make my R/C yacht. You will need a radio system, this includes a transmitter and receiver, then you will need a motor, ESC, servo, battery and charger. ESC stands for Electronic Speed Controller, this goes between the receiver and motor, the reason for this is simply that the receiver and motor speak different “languages”. The servo is a motor that can turn 45 degrees either way, it does the steering. On top of this you will need hardware or hull-fittings. This includes a rudder and mounting bracket, a stinger (this is used were the driveshaft exits the hull, it has a bearing which keeps water out), driveshaft and coupler (to join motor and driveshaft), propeller, a push rod and pushrod boot. The last two join the servo and rudder, the boot keeps water out (see diagram). Click for better resolution (opens in same window)

servo diagram                 To make a hull you will need plywood, balsa (a very light wood which is bendy and can be cut with an x-acto knife), epoxy and glass-fibre cloth. The plywood is used to cut out a deck and bulkheads, bulkheads are what the balsa is glued onto to make it take the hulls curve. The balsa should be about 1-2 mm thick and bendy. It is used to cover the hull, then glass-fibre is applied over it too make it rigid and waterproof.  

PartWhere to get it (link)Price (usd)Quantity
stingerclick here to order this part

$4.06

1
rudder&mounting bracketclick here to order this part

$8.55

1
push/conrodclick here to order this part

$2.66

1
pushrod bootsclick here to order this part

$4.16

1 set
driveshaft set (prop, driveshaft, coupler)click here to order this part

$4.80

1 set
Nylon XT-60 connectorscick here to order this part

$3.99

1 set
hinged couplingclick here to order this part

$4.64

1 set
 Plugs: The ESC comes with a different plug than the battery, that is why you must order the XT-60 connectors, get your hobby shop to solder XT-60 connectors onto the battery and battery wire on the ESC. Also if the motor and ESC have different plugs solder XT-60 connectors onto the motor and the motor wire on the ESC. Here is a diagram of the wiring: Click for beter resolution (opens in same window) tb-boat-page-wiring
PartWhere to get it (link)Price (usd)Quantity
ESCclick here to buy this part

$10.45

1
MotorYou will have to get any 380 SIZED BRUSHED motor. HobbyKing does not stock these so you will need to get this from your hobby shop.1
Radio & Recieverclick here to buy this part

$23.65

1
Servoclick here to buy this part

$3.36

1, I used this one, however you can use any standard sized servo, if you go any smaller it will break under strain.
Batteryclick here to buy this part

$8.40

At least 1, you can get as many as you want. If you order this from HobbyKing the shipping can be very expensive (depending on your location), it could be cheaper to get one from your local hobby shop, they can give you advice on what one to get, IT MUST BE A 2 CELL LIPO
Chargerclick here to buy this part

$22.99

1
 I am writing this as an instruction on purpose, just so that you can better imagine what the process is like and how much work an R/C boat actually is, if you want to make one like this feel free to e-mail me for plans, I can then send you the plans that you can print on A3 paper.

Step one: Draw up the plans on the 10mm plywood, it is recommendable to put the tops of the bulkheads onto the factory cut edge, this makes it easier to attach the frames to the bottom of the deck. Once you have cut out the deck, bulkheads and cabin parts you must attach a bit of square wood to one side of the bulkheads to make the glueing area bigger, now glue the  frames onto the lines marked. Make sure that the middle of the plywood is aligned with the line. Use wood glue and leave at least overnight to dry. Now, the last bulkhead (transom) needs a hole drilled in the centre, one cm from the bottom –mm diameter

Step two: draw a line down the exact centre of the transom. Align the rudder bracket with the line (it it is in the correct place the holes for mounting in the bracket will be out of centre, when looking directly from the back the rudder BLADE will be aligned wit the centre line on the transom. Mark the mounting holes with a pencil and drill them out with a drill as wide as the supplied mounting screws. Now take the stinger and usb it into the hole from the other side when the rudder is mounted, push it in as far as you can and angle it down slightly. Take the rudder back off leave the stinger in place, but whatever you do DO NOT GLUE IT IN YET!

Step three: Now you must install the electronic components. Out of a scrap of 5-10mm plywood cut a board that is as longs the ESC and motor combined plus around 2 cm extra. Glue this to the 3rd bulkhead from the back, ca. 1cm from the bottom tip. Make another plywood board (ca. 5mm thick) that is around 4 by 4cm. Use a small dab of glue to attach it to the front of the plate that you just glued. It should look like another mini bulkhead, let dry over-night. When this is dry hold it in place with your finger and place the motor onto the mounting plate. Then push the motor against the small board until the shaft makes a dent in the word. Now pull the lightly glued board off from the ESC and motor mount. Each and every motor has a small round bump around its driveshaft, measure the diameter of this on your specific motor. Get a drill bit with exactly this diameter and drill it through the small board with the dent using the dent you previously made as a centering aid for the drill. Push the motor in to check for fit. Measure how far each mounting hole is from the outside of the big hump to the centre of the mounting hole, mark these and drill out with a suitable drill, some motors come with the mounting screws, if yours does not then just buy some from a local hardware store. Screw the motor in place and test fit the whole mount. Now use velcro, double sided tape or a cable tie to hold the ESC in place right at the back of the mount. To make the angle, use the flexible coupling mentioned in the hardware list. Now push the drive shaft in from the back through the stinger (you will need to remove the rudder). Align the motor and shaft coupling and tighten the grub screws in the coupler. With this properly aligned you can glue the stinger in from the inside using hot glue and you can now glue the mounting plate as before (with the motor attached), this time with the strongest glue you can find, e.g. epoxy or contact adhesive or just a good amount of wood glue. Super glue will not work. Put a cable tie around the back of the motor. You can also put a bit of foam-rubber underneath the motor to make it quieter.

Step four: Covering! the bulkheads. Cut the balsa sheets to the size of the bulkheads. Leave the length but trim them in width until they fit onto one of the bulkheads sides, trim it to the widest one and leave for the smaller ones. make four planks to fit each of the bulkheads four sides, leave the width for the widest one. Starting at the back, glue the balsa onto the bulkheads using wood glue. Do this for all of the bulkheads but leave it loose by the angled up one. Do this with both of the side ones, not the bottom ones! You can use masking tape to hold the planks in place while they dry overnight. When these are dry trim them from bulkhead to bulkhead using a ruler. Do this by placing the boat on its side with the balsa plank that you are about to cut down. Do this for both sides. After this you can glue the bottom two planks, make sure they are aligned in the centre and sticking over at the outside. Again let these dry over night while being held in place by masking tape. After these have dried again place the boat flat with the balsa strip abut to be cut down on the table and cut the excess off, do this free hand and leave about a millimeter sticking over.

Step five: Put the boat on one of the bottom sides so that the deck opening is facing you, now put a strip of masking tape in the corner where the two planks meet in the centre and on the sides, don’t worry if you can’t get it everywhere. Now flip the boat up-side-down and sand the edges (not the bottom middle) until the little bit of excess is gone, be care full not to sand too much, balsa is very easy to sand and you don’t want a hole the length of your boat.

Step six: Once the sanding is done be care full never to put the boat down on the balsa sides, if you have to, do it on a flat surface and for as short as possible. If there are holes. put MASKING tape over them and sand with 200-400 grit paper until it feels like on smooth surface.

Now you have to start fibre glassing the hull. Use any CLOTH, not MAT, your hobby store will be able to recommend you some.

You can now cut the cloth into rectangles – any size you are comfortable with, use the sharpest scissors you have and do it slowly.
Now mix the epoxy to the directions ratio. Once that is done gently lay the cloth onto the boat and mark its size onto the balsa with a pencil. Remove the cloth and paint a thin layer of epoxy onto the marked area. Now place the cloth onto the epoxy making sure all the edges are in the epoxy too, if necessary lift up the edge and paint some more epoxy under there. Leave to set for around 2 mins.

Now gently paint another thin coat of epoxy over the top so that the whole cloth is covered. Keep doing this until you have used up your batch of epoxy. Make sure that the cloth pieces over lap.

FOR THE EDGES: PAINT THE EPOXY DIRECTLY ONTO THE HULL – THIS TIME A THICKER LAYER AND LEAVE TO SET UNTIL TACKY, THIS USUALLY TAKES AROUND 5 MINS. THEN BEND THE  CLOTH OVER AND PRES INTO THE EPOXY FIRMLY HOLD IT THERE UNTIL IT WILL NOT COME LOOSE. ALSO MAKE SURE THAT THERE IS ALWAYS AT LEAST 3-4 CM STICKING OVER, NOT JUST A COUPLE OF FIBERS – THESE GO HARD AND ARE A NUISANCE. ALSO MAKE SURE THAT THERE ARE NO AIR BUBBLES!!

Do this until every single little bit of the wood is covered with the fibre glass – you should have at least two layers and you will need a third if you plan on putting in a bigger motor, if you do so don’t go higher than a 540 sized motor. Let every bit of the glass fibre dry overnight. Once you have checked the hull, pay extra  attention to areas like where the stinger exits the hull, the rudder mount.

Now attach the servo horn to the pushrod and the whole thing can then be pushed through the whole in the transom from the inside. Clip the horn onto the servo and slide the rubber boot over the rod until it sits uncompressed and unexpanded in the hole when the servo horn points straight up.
The pushrod boot is like a mini bellows and has one small end and one big end, the big end is pushed into the hull after fibreglassing and is then epoxied in place by covering the joining area with epoxy.
pushrodboot

This can be done by simply dipping rod in epoxy and rubbing it onto the joint. When the pushrod is sticking out the back you can fix it to the linkage stopper by putting it through the whole and tightening the grub screw in the top with an allan/hex key.

Here is a picture of the rudder, prop and stinger all under the diving platform. The hose coming up from the rudder is for water cooling, this is not needed for our purposes as it is not a speedboat and the electrics won’t heat up too much.
transom rc yacht


Comments

The Big Floating Project — No Comments

Leave a Reply

Your email address will not be published.

The maximum upload file size: 128 MB. You can upload: image, audio, video, document, spreadsheet, interactive, text, archive, code, other. Links to YouTube, Facebook, Twitter and other services inserted in the comment text will be automatically embedded. Drop file here

HTML tags allowed in your comment: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>